Android tablet disconnects from WiFi when attempting to cast to Chromecast Audio

[binarydad]

I'm not sure where to start, but I can't seem to find any info on this one. I do have a N66U, and it is a wireless issue, so I'll start here.

I have a Samsung Tablet (android 7.0) and a LG G5 (android 7.0). I have 4 CCAs. Ever since the tablet was upgraded to 7.0, it's had an issue where, about half the time, once I select a device to cast to from Spotify/Pandora (either one), it disconnects the WiFi on the tablet. It will physically turn the wifi off, and it will come back on after about 20 seconds. After then it will work.

The LG G5 has never had this issue.

The CCAs are on the 2.4GHz band, the tablet is on 5Ghz, and the LG G5 is on 2.4Ghz. I can't figure out why one device has the issue and the other doesn't, then I realized that the CCAs and the tablet are on the same network band. Maybe this suddenly has something to do with it? I'm currently experimenting with putting the CCAs on 2.4Ghz and leaving the tablet on 5Ghz, but I can't understand why this even could be an issue.

My N66U firmware is pretty old, but I kept it old for performance reasons, and have been hesitant to update it. Also, I've already tried a factory reset on the tablet and factory resets on each CCA with no change in behavior.

Could someone shed some light on what is happening when I attempt to cast? Why could it disconnect my tablet WiFi? Would upgrading my WAP help?

Thanks.

 

[binarydad]

More on the experiment. I put the CCAs on 2.4 and my tablet on 2.4, and it did the same behavior. I'm currently testing it with them each on different WiFi bands (CCAs 2.4, tablet 5ghz). So far it seems stable. The issue seems to be if this one tablet is on the same band as the CCAs. Very weird. Any ideas??

Also, I updated my router's FW to the latest. Still no luck.